PASCAGOULA, Mississippi -- Corrine Heathcock, the mother of Jonathan Chase DeBlase and Natalie Alexis DeBlase, said Monday that she is holding out hope that her children will be found alive.

"Until the police come to me and say they have their bodies, I won't believe it," said Heathcock, 27. "If they do tell me that, then I want to bury them together. They were always inseparable. I couldn't separate them in death."

Authorities said they believe Jonathan, 3, and Natalie, 5, are dead, and their bodies were dumped, one in Vancleave and one in Citronelle, Ala.

Their father, John Joseph DeBlase, 27, and stepmother, Heather Leavell-Keaton, 22, face criminal charges in connection with the case but have not been charged with killing the children.

Authorities said the 2 children haven't been seen since they moved to Kentucky with their father and stepmother, but the exact time appears to be unclear.

Mobile Police Chief Micheal T. Williams said late Monday that family members have told detectives that the last time they saw the children was in February.

"I know there are saying my children have not been seen since June or July, but I don't think that's right," Heathcock, who lives in Mobile, said Monday afternoon. "I've talked to his family members and a mutual friend that said they saw Jonathan and Natalie in September."

Heathcock said DeBlase was a good person when they were married, and he loved their children, but changed shortly after he married Leavell-Keaton.

"Before, he would have never dreamed of hurting his children," Heathcock said of her ex-husband. "I don't want to think that's what he's done now."

Heathcock said her friends, family and current husband are the reason she gets up every morning.

"They are keeping me going," Heathcock said. "This is hard enough, but then you throw in people criticizing me, too. It's almost unbearable."

Heathcock said when she and DeBlase divorced, she made the best possible choice for Jonathan and Natalie.

"I wasn't living in a place that was suitable for children," Heathcock said. "He was the best thing for them. He loved them. I would have never let him take them if I thought otherwise."

Heathcock said things were fine for a while, then DeBlase quit letting her see Jonathan and Natalie.

"He'd make up excuses why I couldn't see them," she said, sobbing. "He'd forget to bring them over. He, eventually, stopped answering his phone."

Heathcock said she last saw her children on Nov. 18, 2009.

She said Natalie was full of laughter, and Jonathan was a tiny lady's man.

"We took them to a park with my family," Heathcock said. "We all were swinging and sliding, just having fun. The last thing they did was wrap their arms around my neck and tell me they loved me so much."

Heathcock said she believes Jonathan and Natalie will be found alive and she begged anyone with information to contact authorizes.

"When they are found, I want them back," Heathcock said.

Anyone with information in the case is asked to call the Mobile Police Department at 251-208-7211